Subject: Yellow or Anise Swallowtail
Geographic location of the bug: West Los Angeles
Time: 05:47 PM EDT
Your letter to the bugman: Hi Bugman,
Is this a yellow swallowtail or an anise swallowtail (or are they the same)? She’s laying her eggs on a fennel plant.
How you want your letter signed: Jeff Bremer
Please forgive our tardy response. According to the Jeffrey Glassberg book Butterflies Through Binoculars The West, the Anise Swallowtail has both a dark and a light or yellow form, and they are not designated as distinct subspecies. The two color forms exist over much of the species’ range. According to BugGuide, there are two subspecies and BugGuide notes: “There has been a lot of debate over the years as to whether the inland populations of P. zelicaon are different enough to consider as a distinct subspecies from ‘typical’ zelicaon from closer to the Pacific. Also, it is debated, assuming there is a difference, just what the difference is, and where one population begins and the other ends.” We always appreciate your butterfly submissions and we are tagging this submission of an Anise Swallowtail as our Bug of the Month for June 2020. As a side note, Daniel was excited to find a young Anise Swallowtail caterpillar on a dill umbel in his garden and he watched it grow over the course of a week, only to have it vanish. The suspected culprit is a Paper Wasp seen patrolling the dill plant the day the caterpillar vanished.